, power law, switches and loads, wiring diagrams, electronic components and electrical ... tools and materials. Principles of roof design and drainage systems. ... Calculation of downspout and gutter sizes. Fabrication ... of drainage components and weather sealing ... , pattern layout, and fabrication of selected ductrun fittings. ... . Planning, testing, and installation of specific types of drains. Prerequisites ... : None. IMC121 Water Supply and Accessories 1 Credit 1 ... Period Water main and valve installation. Assembly and installation ... of valves and water heaters. Prerequisites: None. IMC122 Piping ... 1 Credit 1 Period Principles and design of duct systems, construction layout, ... , and applications. Fabrication of select sheet metal fittings. ...